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View Full Version : Another Forced Landing issue.


okeydokey
20th Jan 2002, 17:37
There seems to be 2 schools of thought on inital actions (disregarding checks) to be taken during an engine failure in a single.
-Raise the nose immediately to convert speed(assuming cruise) into altitude.

or

-trim the nose attitude to glide (ie: maintain straight and level for a limited period prior to glide).

Any thoughts on which is preffered, please include reasons. <img src="cool.gif" border="0">

BEagle
20th Jan 2002, 18:30
There is insufficient kinetic energy in most light ac at cruising speed to convert into the potential energy of altitude - 'converting speed to height'. The best solution is to fly the ac in the most energy-conserving manner until the IAS reduces to the normal gliding IAS - i.e. don't manoeuvre energetically to achieve gliding speed and avoid causing any buffet. It's simplest just to maintain cruising attitude and then to adjust gently to the attitude for best gliding IAS as the speed bleeds off.

DB6
20th Jan 2002, 21:48
Depends on your height and situation at the time but I'd generally agree with Beagle; you'd only get a couple of hundred feet at best by converting speed to height and if you're already at 3000' then it's not worth it. If however you're at ~1000' or below then it could mean the difference between making your field or not, especially if you're fast at the time and therefore have spare kinetic energy to convert into potential, which is what it comes down to.

BEagle
21st Jan 2002, 00:25
DB6 - yes, perhaps if at very low level (for civvies) and at sufficient speed (e.g. 120 KIAS in the 'dog - nearly 50 KIAS above the gliding speed), a gentle pull up to assess the best survivable crash site was probably worthwhile. Probably a good reason not to fly a light ac at low level unless you're continuously aware of available forced landing spots!

foxmoth
21st Jan 2002, 03:16
This one REALLY is dependant on the aircraft and how it is being flown at the time, I think most people have been saying much the same. If you have LOTS of speed in hand then convert it, if you are only 20Kts or so above your glide speed it is probably not worth bothering - just hold your attitude, look at the situation you have and use common sense to decide.

Checkboard
25th Jan 2002, 09:34
I always taught the "raise the nose, convert XS speed to height" technique, not because it was more efficient, but simply because it allowed the student to trim for the best gide speed as soon as possible.

This allowed them to concentrate on their failure checks, without too much concern for aircraft handling. Spending a minute or sow maintaining level flight, waiting for glide speed, seemed like a waste of time, while the "XS speed to height" thing gets them thinking about their glide speed immediately, and it covers all situations.